I would guess that the vets examined the crocodile, and through the aid of a stethoscope, were able to hear the ringing phone.
Either that, or she has a very loud and obnoxious ringtone!
my 3 year old (2 at the time) “helped” me by bringing my ringing cell phone to me in the bath once, and promptly dropped it in...it stopped ringing immediately, and never rang again. In fact, it never turned on again. They do make cell phones that can survive water and being dropped and whatnot. They are ugly and my hubby threatens me with them every time I do something to mine (like setting it in the little niche where the windshield wipers live while putting the wipers back after a snowy night and forgetting it and driving off). Maybe she had an “indestructible phone”.